Iron-phosphorus-silicon alloy



. promising.

Patented July 14, 1942 UNITED STATES PATENT OFFICE 2,289,365 IRON-PHOSPHORUS-SILICON ALLOY Henry S. Jerabek, Minneapolis, Minn.

No Drawing. Application August 29, 1941, Serial No. 408,859

(Granted under the act amended April 30, 19

12 Claims.

the conditions of operation of the phosphate reduction furnace in which they are produced. These iron-phosphorus alloys are useful to a limited extent in the production of steels, but.

the further utilization of such alloys in substan tial proportions to produce useful articles of manufacture has not hitherto been The alloys of the present invention are composed of the following essential constituents in approximately the proportions stated: 2 to 13% phosphorus, 6 to 22% silicon, the total of the phosphorus and silicon being not more than approximately 26%, with the all iron. Alloys conforming to theabove composition may contain up to 35% of a metal selected from the group consisting of aluminum, chromium, copper, manganese, molybdenum, nickel, titanium, and vanadium substituted for part of such iron.

A preferred narrower range of the essential constituents is asfollows: to 10% phosphorus, 10 to silicon, with the balance substantially all iron, or up to 25% of a metal selected from the foregoing group substitutedfor a part of the iron.

The alloys of the present invention are suitable for casting to form articles of manufacture which are particularlycorrosion resistant and, therefore, suitable for, producing articles suchas acid pumps, acid conduits, and the like. The alloys so produced have' been found particularly resistant to attack in contact with 80% orthophosphoric acid at 240 F., 90% orthophosphoric acid of March 3, 1883. as

at 280 F., boiling hydroc loric acid, and boiling 30% sulfuric acid.

Ferrophosphorus produced under a wide range, plant scale, phosphate reduction furnace operation has been found to have the following approximate compositions:

Per cent The impurities which are present in all electric particularly balance substantially furnace ferrophosphorus are shownby the following typical analyses:

P Si Mn Ti A] C I S 13. 7 17. 5 3. 5 1. 0 0. 1 Tr. Tr. 17. 4 12. 7 3. 5 1. 3 0. 2 Ti. Tr. 25. 1 0. 9 3. 5 1. 1 0. 2 Tr. Tr.

Such commercial ferrophosphorus has been used to produce the alloys of the present invention in conjunction with other metals or alloys as follows:

Armco ingot iron.Typical analysis-99.78 perv cent Fe, 0.013 percent C, 0.02 per cent Mn, 0.002 per cent P, 0.001 per cent Si, 0.04 percent Cu, and 0.02 per cent Ni.

'Silic0n.-Ana1ysis-99.79 per cent Si, 0.027 per cent Fe, 0.003 per cent Al, 0.01.4 per cent Ca, 0.004 per cent C, 0.10 per cent N2.

Low-carbon jerrochrome.-7l.5 per cent Cr, 0.16 per cent C mesh). Nickel shot .(98-99 per cent Ni) .Analysis- 0.4-0.7 per cent Fe, 0.1-0.3 per cent Cu, 0.15-0.6 per cent C, 0.15-0.3 per cent Si.

C'opper.--High conductivity cent Cu-typical analysis.

Molybdenum-Powdered. Ferrovanadium (51 per cent V) .-Typical analysis-6 per cent Mn, 10 per cent $1, 1.6 per cent 0, 1 per "sent 5.

grade 9913+ per Charges of predetermined composition were melted in a zircon lined alundum or graphite crucible and poured into open top cast iron molds.

Castings were removed quickly from the mold Alloy No. Com sition Impact tests on specimens of alloys Nos. 42, 42A, 45, 47 and the last alloy in the immediately preceding table in a Charpy impact machine showed foot pounds absorbed 5, 2, 1, 2.4 and 3.6, respectively, using x 10 x 510 mm. specimens, with a notch 1 mm. deep and 1.5 mm. radius.

5. An alloy comprising the following elements in approximately the proportions given (a) 2 to 13% phosphorus,

Hardness tests on alloys Nos. 42, 42A, 45, 47 and 47A by a Shore scleriscope gave an average Shore hardness number of 91, 96, '72, 96 and 94,

respectively. These latter results may be compared with those values for properly hardened tool steel, 91 Shore, and Stellite, 85 Shore. These specimens were too brittle for Rockwell tests.

I claim:

1. An alloy comprising the following elements in approximately the proportions given (a) 2 to 13% phosphorus,

(b) 6 to 22% silicon, the total of the phosphorus and silicon. being not more than approximately 26%,

(c) the balance substantially all iron.

2. A corrosion resistant article of manufacture formed of a metal alloy comprising the following elements in approximately the propor tions given (a) 2 to 13% phosphorus,

(b) 6 to 22% silicon, the total of the phosporus and silicon being not more than approximately 26%,

(c) the balance substantially all iron.

3. An alloy comprising the following elements in approximately the proportions given (a) 7.5% phosphorus,

(b) 12.5% silicon,

(c) the balance substantially .all iron.

(b) 6 to 22% silicon, the total of the phosphorus and silicon being not more than approxi-' mately 26% and (0) up to 35% aluminum,

(d) the balance substantially all iron.

6. An alloy comprising the following elements in approximately the proportions given (a) 2 to 13% phosphorus (b) 6 to 22% silicon, the total of the phosphorus and silicon being not more than approximately 26% and (0) up to 35% chromium,

(d) the balance substantially all iron.

7. An alloy comprising the following elements in approximately the proportions given (a) 2 to 13% phosphorus,

(b) 6 to 22% silicon, the total of the phosphorus and silcon being not more than approximately 26% and (0) up to 35% copper,

(d) the balance substantially all iron.

8. An alloy comprising the following elements in approximately the proportions given (a) 2 to 13% phosphorus,

(b) 6 to 22% silicon, the total of the phosphorus and silicon being not more than approximately 26% and (0) up to 35% manganese,

(d) the balance substantially all iron.

9. An alloy comprising the following elements in approximately the proportions given (a) 2 to 13% phosphorus,

(b) 6 to 22% silicon, the total of the phosphorus and silicon being not more than approximately 26% and (0) up to 35% molybdenum,

(d) the balance substantially all iron.

10. An alloy comprising the following elements in approximately the proportions given (a) 2 to 13% phosphorus,

(b) 6 to 22% silicon,-the total of the phosphorus and silicon being not more than approximately 26% and (0) up to 35% nickel,

(d) the balance substantially all iron.

11. An alloy comprising the following elements in approximately the proportions given (a) 2 to 13% phosphorus,

(b) 6 to 22% silicon, the total of the phosphorus and silicon being not more than approximately 26% and (0) up to 35% titanium,

(d) the balance substantially all iron.

12. An alloy comprising the following elements in approximately the proportions given (a) 2 to 13% phosphorus,

(b) 6 to 22% silicon, the total of the phosphorus and silicon being not more than approximately 26% and (0) up to 35% vanadium,

(d) the balance substantially all iron.

HENRY S. JERABE'K. 

